The facts
What spectrolite actually is
Spectrolite is classified as labradorite (plagioclase feldspar), with the composition (Ca,Na)(Al,Si)₄O₈. It crystallises in the triclinic system.
Colour comes from full-spectrum labradorescence on a near-black body, from unusually varied lamellar thicknesses, which is also what a laboratory looks at when it is asked whether a colour is natural.
Refractive index 1.559–1.570. Specific gravity around 2.68–2.72. Cleavage: perfect {001}, good {010}. Those three numbers separate it from most of what imitates it.
Where spectrolite comes from
Spectrolite is produced at Ylämaa, South Karelia, Finland.
That is the whole list. A single source makes supply fragile and makes any claim of a second origin worth questioning.
How spectrolite is treated
Untreated. 'Spectrolite' is properly a Finnish trade name for the Ylämaa deposit; Madagascan labradorite is widely sold under the name, which is misdescription rather than treatment.
Treatment changes value, sometimes by a multiple, so it belongs in the description before the price and not after the sale.
What spectrolite is confused with
In the trade spectrolite is most often mistaken for, or substituted by, Labradorite, Ammolite or Coated glass.
The separation is rarely a matter of opinion: refractive index 1.559–1.570 and specific gravity 2.68–2.72 settle most of it in a minute, and magnification settles the rest.
What spectrolite is used for
Demand for spectrolite comes from jewellery, carving and sculpture, architecture and interiors, decorative objects and mineral collecting, which is why one price per carat never covers it.
We quote each application in the unit that trade actually buys in, by the carat, by the block or by the square metre.
Durability and care
Spectrolite is 6–6.5 on the Mohs scale, with perfect {001}, good {010} cleavage.
Hardness is not the whole story. Perfect cleavage means the stone can split cleanly if struck along the wrong plane, whatever its Mohs number, so a protective setting matters more here than the hardness suggests.
Warm water, mild soap and a soft brush. Avoid ultrasonic cleaners on anything fracture-filled, stabilised, dyed or visibly included.
What spectrolite costs
As a guide, spectrolite trades around $2–40/ct.
That is a range, not a quote. Colour, size, clarity, cut and origin move the figure a long way inside it, and the only honest price is one given against a specific stone. Send us what you need and we will price it.
Questions
Is spectrolite treated, and how?
Untreated. 'Spectrolite' is properly a Finnish trade name for the Ylämaa deposit; Madagascan labradorite is widely sold under the name, which is misdescription rather than treatment.
Where does spectrolite come from?
Ylämaa, South Karelia, Finland. That is the only commercial source.
Is spectrolite hard enough to wear every day?
With care. It is 6–6.5 on the Mohs scale, which is hard enough, but perfect {001}, good {010} cleavage means it can split if struck at the wrong angle. Use a protective setting and avoid ultrasonic cleaning.
How much does spectrolite cost?
Indicatively $2–40/ct. Colour, size, clarity and origin move the price a long way within that, so treat it as a range and ask for a quote against a specific stone.
What is spectrolite confused with?
Most often Labradorite, Ammolite and Coated glass. A refractive index of 1.559–1.570 and a specific gravity near 2.68–2.72 separate it quickly.
What is spectrolite used for besides jewellery?
carving and sculpture, architecture and interiors, decorative objects and mineral collecting. Each of those trades buys it in a different form and a different unit.
Related stones
Looking for spectrolite?
Tell us the size, the quality and what it is for. We source it, photograph it and quote it — with the locality named.
Ask about spectrolite